Radio frequency(RF)cavities for advanced storage rings,also known as diffraction-limited storage rings,are under development.To this end,a competitive and promising approach involves normal-conducting continuous wave ...Radio frequency(RF)cavities for advanced storage rings,also known as diffraction-limited storage rings,are under development.To this end,a competitive and promising approach involves normal-conducting continuous wave technology.The design and preliminary test of a 499.654 MHz RF cavity for the Wuhan Advanced Light Source(WALS)based on specific beam parameters were conducted at the SSRF.Multi-objective evolutionary algorithms have been utilized to optimize RF properties,such as the power loss and power density,resulting in better performance in the continuous wave mode.Further improvements were made to suppress multipacting effects in the working area.To operate stably with the beam,higher-order mode dampers were applied to better address the coupling bunch instability than in previous designs,along with thermal analysis to achieve the desired RF performance.Comprehensive simulation studies demonstrated the stable operation of the RF cavity at the defined beam parameters in the WALS design.A prototype RF cavity was then developed,and the RF performance results in a low-power test showed good agreement with the design and simulation,exhibiting readiness for high-power experiments and operation.展开更多
In recent years,due to the scarcity of domestic radioisotopes,the Chinese government has strongly supported the development of dedicated radioisotope production facilities.This paper presents conceptual design simulat...In recent years,due to the scarcity of domestic radioisotopes,the Chinese government has strongly supported the development of dedicated radioisotope production facilities.This paper presents conceptual design simulations of an 11 MeV,50μA,H^(-) compact superconducting cyclotron for radioisotope production.This paper focuses primarily on four aspects:magnet system design,central region configuration,beam dynamics analysis,and extraction system design.This paper outlines the cyclotron's primary parameters and key steps in the development process.展开更多
Most synchrotron light storage rings are equipped with a higher harmonic cavity(HHC)and are currently predominantly used to increase beam life.With the enhancement of the beam current intensity,it is necessary to cons...Most synchrotron light storage rings are equipped with a higher harmonic cavity(HHC)and are currently predominantly used to increase beam life.With the enhancement of the beam current intensity,it is necessary to consider instability problems that may be caused by heavy beam loading effects.In this study,we incorporated a HHC into the small-signal Pedersen mathematical model and used system signal analysis to investigate the mode-zero Robinson instability driven by the passive superconducting harmonic cavity and active superconducting harmonic cavity fundamental modes.To further study and alleviate this instability,we introduced direct radio-frequency feedback,an automatic voltage control loop,and a phase-lock loop into the model,discussed the impact of the feedback loop parameter settings on the stability margin,and provided suggestions for parameter settings.展开更多
基金supported by National Natural Science Foundation of China(Nos.12222513,12105345,12175292,and No.12405178)。
文摘Radio frequency(RF)cavities for advanced storage rings,also known as diffraction-limited storage rings,are under development.To this end,a competitive and promising approach involves normal-conducting continuous wave technology.The design and preliminary test of a 499.654 MHz RF cavity for the Wuhan Advanced Light Source(WALS)based on specific beam parameters were conducted at the SSRF.Multi-objective evolutionary algorithms have been utilized to optimize RF properties,such as the power loss and power density,resulting in better performance in the continuous wave mode.Further improvements were made to suppress multipacting effects in the working area.To operate stably with the beam,higher-order mode dampers were applied to better address the coupling bunch instability than in previous designs,along with thermal analysis to achieve the desired RF performance.Comprehensive simulation studies demonstrated the stable operation of the RF cavity at the defined beam parameters in the WALS design.A prototype RF cavity was then developed,and the RF performance results in a low-power test showed good agreement with the design and simulation,exhibiting readiness for high-power experiments and operation.
文摘In recent years,due to the scarcity of domestic radioisotopes,the Chinese government has strongly supported the development of dedicated radioisotope production facilities.This paper presents conceptual design simulations of an 11 MeV,50μA,H^(-) compact superconducting cyclotron for radioisotope production.This paper focuses primarily on four aspects:magnet system design,central region configuration,beam dynamics analysis,and extraction system design.This paper outlines the cyclotron's primary parameters and key steps in the development process.
文摘Most synchrotron light storage rings are equipped with a higher harmonic cavity(HHC)and are currently predominantly used to increase beam life.With the enhancement of the beam current intensity,it is necessary to consider instability problems that may be caused by heavy beam loading effects.In this study,we incorporated a HHC into the small-signal Pedersen mathematical model and used system signal analysis to investigate the mode-zero Robinson instability driven by the passive superconducting harmonic cavity and active superconducting harmonic cavity fundamental modes.To further study and alleviate this instability,we introduced direct radio-frequency feedback,an automatic voltage control loop,and a phase-lock loop into the model,discussed the impact of the feedback loop parameter settings on the stability margin,and provided suggestions for parameter settings.
